Definition a square = b square root of b = a. 2. Seperate square root or 9 over 16 rewrite by splitting up square root of 9 divided by the square root of 16 since 9 and 16 are perfect square root u will get a whole number. what number equals 9 when you square root it? 3 what number equals 16 when you square root it is 4. then u get 3 over 4. 3. Rewrite we had originally the square root of 9 over 16 and we found by splitting up our square root signs that is equal to 3 over 4. Remember when your taking the square root of a fraction simply break up the fraction into its numerator and denominator and find the square root of the nominator and denominator.